Material Flow Accounting: Measuring Global Material Use for Sustainable Development
The growing extraction of natural resources and the waste and emissions resulting from their use are directly or indirectly responsible for humanity approaching or even surpassing critical planetary boundaries. A sound knowledge base of society's metabolism, i.e., the physical exchange processes between society and its natural environment and the production and consumption processes involved, is essential to develop strategies for more sustainable resource use. Economy-wide material flow accounting (MFA) is a framework that provides consistent compilations of the material inputs to national economies, changes in material stocks within the economic system, and material outputs to other economies and the environment. We present the conceptual foundations of MFA and derived indicators and review the current state of knowledge of global patterns and trends of extraction, trade, and use of materials. We discuss the relation of material use and economic development and the decoupling of material use from economic growth in the context of sustainable resource use policies.

Urban Economies Resource Productivity and Decoupling: Metabolism Trends of 1996--2011 in Sweden, Stockholm, and Gothenburg
Resource productivity and evidence of economic decoupling were investigated on the basis of the time series in 1996-2011 of material flow analysis for Sweden, Stockholm, and Gothenburg. In the three cases, absolute reductions in CO2 emissions by about 20% were observed, energy consumption per capita decreased, while gross domestic product (GDP) per capita grew. The energy consumption of the residential and public sectors decreased drastically, while the transport energy consumption is still growing steadily. Decoupling of the economy as a whole (i.e., including materials) is not yet happening at any scale. The domestic material consumption (DMC) continues to increase, in parallel with the GDP. The rate of increase for DMC is slower than that for GDP in both Stockholm and Sweden as a whole (i.e., relative decoupling). The metabolism of the cities does not replicate the national metabolism, and the two cities each have their own distinct metabolism profiles. As a consequence, policy implications for each of the case studies were suggested. In general, because of the necessarily different roles of the two cities in the national economy, generic resource productivity benchmarks, such as CO2 per capita, should be avoided in favor of sectorial benchmarks, such as industry, transport, or residential CO2 per capita. In addition, the share of the city impacts caused by the provision of a service for the rest of the country, such as a port, could be allocated to the national economy.

Decoupling Economic Growth and Environmental Degradation: Reviewing Progress to Date in the Small Island State of Malta
This paper considers the challenge of decoupling economic growth from environmental degradation; in contrast to several large-scale cross-country analyses that focus on limited indicators of environmental degradation, we analyze in some depth the experience of a single small-scale island state setting (Malta). We use available statistical data to derive decoupling factors, in order to consider the extent to which decoupling has been achieved in four sectors: (i) energy intensity, climate change, and air quality; (ii) water; (iii) waste; and (iv) land. Results indicate relative decoupling between economic growth and several indicators considered, and to a lesser extent, relative decoupling between population growth and the same indicators of environmental pressure. Absolute decoupling has been achieved in at least one instance but there has been no decoupling of land development from either economic or population growth. Land use and population thus appear to be notable sources of pressure. The results suggest that decoupling analyses that present environmental degradation in terms of single variables (e.g., carbon emissions) may misrepresent somewhat the state of the environment at local level. Furthermore, the study highlights the need for methodologies that factor in the “embedding” of small-scale settings within much larger trade networks, for a more accurate estimation of environmental impact, and points to some limitations of solely quantitative analyses of environment-ecology relationships.

The role of in-use stocks in the social metabolism and in climate change mitigation
Human well-being includes the use of physical services from buildings, infrastructure, and consumer products. These in-use stocks link the services enjoyed by humans to energy and material consumption. Climate change mitigation requires us to transform current in-use stocks to decouple energy and material throughput from service provision. Assessing the potential environmental benefits of emissions mitigation and other sustainable development strategies requires a solid understanding of in-use stocks and their dynamics. We identified the different roles of in-use stocks in the social metabolism and showed to what extent they are included in current impact assessment models. We extended state-of-the-art dynamic stock models by including direct and indirect energy demand and greenhouse gas emissions. We applied the new modeling framework to three case studies in the major sectors transportation, buildings, and industry. We assessed the emissions reduction potential of the decoupling strategies energy efficiency, material efficiency, and moderate lifestyle changes. For the global steel industry and for residential buildings the emissions reduction potential of the above-mentioned strategies was so large that the benchmarks corresponding to the 2 °C climate target could be reached. Decoupling alone might be sufficient to reach the 2 °C benchmarks in some sectors. Considering decoupling next to supply side measures such as new energy technologies may make it easier to consider other objectives than emissions reduction. Decoupling may therefore revitalize the debate about sustainable development because it allows us to loosen the focus on climate change mitigation and put more weight on the economic, social, cultural, and other environmental aspects of sustainability.

Decoupling Economic Growth and Environmental Degradation: Reviewing Progress to Date in the Small Island State of Malta
This paper considers the challenge of decoupling economic growth from environmental degradation; in contrast to several large-scale cross-country analyses that focus on limited indicators of environmental degradation, we analyze in some depth the experience of a single small-scale island state setting (Malta). We use available statistical data to derive decoupling factors, in order to consider the extent to which decoupling has been achieved in four sectors: (i) energy intensity, climate change, and air quality; (ii) water; (iii) waste; and (iv) land. Results indicate relative decoupling between economic growth and several indicators considered, and to a lesser extent, relative decoupling between population growth and the same indicators of environmental pressure. Absolute decoupling has been achieved in at least one instance but there has been no decoupling of land development from either economic or population growth. Land use and population thus appear to be notable sources of pressure. The results suggest that decoupling analyses that present environmental degradation in terms of single variables (e.g., carbon emissions) may misrepresent somewhat the state of the environment at local level. Furthermore, the study highlights the need for methodologies that factor in the “embedding” of small-scale settings within much larger trade networks, for a more accurate estimation of environmental impact, and points to some limitations of solely quantitative analyses of environment-ecology relationships.

Re-estimating the decoupling effect: Is there an actual transition towards a less energy-intensive economy?
The historical issue of the natural resources scarcity is revived currently through the empirical investigation into the dependence of the modern economy on the inputs of material and energy. The contemporary debate on de-growth and a-growth feeds on the empirical assessments of the relationship between energy-material use and current growth trends. In this context, the present study attempts a re-estimation of the energy-economic growth decoupling effect taking into account the physiology and, hence, the dimensionality that economic goods have. The Energy/GDP per Capita ratio is proposed as an indicator that approximates better than the Energy/GDP ratio the real world properties of production and, therefore, its energy requirements. The resulting estimations of decoupling effect are less 'optimistic' than those based on Energy/GDP ratio and prevalent in the relevant contemporary literature.

City-Level Decoupling: Urban resource flows and the governance of infrastructure transitions
Building upon previous work of the International Resource Panel on Decoupling Natural Resource Use and Environmental Impacts from Economic Growth, this report examines the potential for decoupling at the city level. While the majority of the world's population now live in cities and cities are where most resource consumption takes place, both the pressures and potentials to find ways to reconcile economic growth, wellbeing and the sustainable use of natural resources will therefore be greatest in cities. Analysing the role of cities as spatial nodes where the major resource flows connect as goods, services and wastes, the report ‘s focus is how infrastructure directs material flows and therefore resource use, productivity and efficiency in an urban context. It makes the case for examining cities from a material flow perspective, while also placing the city within the broader system of flows that make it possible for it to function. The report also highlights the way that the design, construction and operation of energy, waste, water, sanitation and transport infrastructures create a socio-technical environment that shapes the 'way of life' of citizens and how they procure, use and dispose of the resources they require. Its approach is innovative in that it frames infrastructure networks as socio-technical systems, examining pressures for change within cities that go beyond technical considerations. The importance of intermediaries as the dominant agents for change is emphasized, as well as the fact that social processes and dynamics need to be understood and integrated into any assessment of urban infrastructure interventions and the reconfiguration of resource flows. A set of 30 case studies provide examples of innovative approaches to sustainable infrastructure change across a broad range of urban contexts that could inspire leaders of other cities to embrace similar creative solutions. Of course, innovations in and of themselves do not suffice if they are not integrated into larger strategic visions for the city, and as each city is unique, interventions need to be tailored to the set of challenges and opportunities present in each case.

Material use and material efficiency in Latin America and the Caribbean
Different world regions have followed very different trajectories for natural resources use over the recent decades. Latin America has pursued a development path based largely on exports of primary resources. Adopting this path has characteristic environmental and social impacts. In this paper, we provide the first broad based estimate of material use and material efficiency for the region, beginning in 1970 and extending to the onset of the global financial crisis in 2008. The results show a region with rapidly growing primary materials consumption, which is simultaneously becoming less efficient at converting those resources into national income. Using an IPAT framework, we found that population growth and rising per-capita incomes made comparable contributions to growing material use, while technological change as reflected in material intensity, did not moderate consumption. Increasing materials intensity, observed for the region as a whole, is also observed for most individual countries. This contrasts with some other world regions, and implies that many countries in Latin America and the Caribbean will confront higher environmental pressures than expected when expanding their extractive industries to take advantage of new demand from other world regions, while simultaneously supplying the requirements for their own domestic industrial transformations and urbanization.

Material flow accounting in an Irish city-region 1992-2002
This paper aims to measure raw material inputs and waste flows in an Irish city-region in order to analyse (i) whether there was absolute dematerialisation in the particular case study over the period 1992-2002 and (ii) whether material consumption and waste generation were decoupled from economic growth and increases in disposable income over the same period. It was found that the selected material flow indicators showed no evidence of absolute dematerialisation over the given study period, although more recent evidence at the national level suggests that a decline in construction activity and extraction of non-metallic minerals has resulted in an absolute reduction in material consumption and it is likely that this will be mirrored at the system boundary level. It was found that Domestic Material Consumption (DMC) per capita and Direct Material Input (DMI) per capita increased at a faster rate than Domestic Processed Output (DPO) per capita and Direct Material Output (DMO) per capita between 1992 and 2002, which indicates relative decoupling of consumption from waste generation. In addition, it was found that there was relative decoupling of consumption and waste generation from disposable income growth over the study period. Finally, it was found that average DMC and DMI figures for the selected case study were lower than the national averages but broadly similar to results for other city-regions in the European Union (EU). On a methodological note, it was concluded that material flow accounting (MFA) for city-regions in Ireland is constrained due to a lack of disaggregated data for material flows, with the exception of local waste data, and it is recommended that bottom-up analysis should be used to complement disaggregated top-down data.